Plug valve casing head



Oct 25, 1938- F. I.. PlvoTo I PLUG VALVE CSlNG Filed Nov.v 4, 1955 Patented Oct. 25, 1938 UNITED STATES PATENT GFFICE n PLUG VALVE CASING HEAD Felix L. Pivot, Liberty, Tex. Application November 4, 1935, Serial No. 48,202

5 Claims. (Cl. 166-15) The invention relates to an improvement in casing heads for wells and particularly of the type where high pressures are encountered in the formations drilled.

Various types of casing head constructions have been devised heretofore. It is the usual practice, however, to provide the casing head for connection to the well'casing and to provide lseparate valves for closing the passagesthrough the casing and tubing which are to be mounted above the casing head and which general assembly is known in the eld as a Christmas tree.

The present arrangement contemplates a combination casing head and valve construction so that a valve to control theliiow of uid from the casing and a valve to control the iiow of iluid from the tubingwill both be carried by the same unitary construction so that compiete control of the well can be had by the use of this one construction. y

It is intended that this plug valve casing head can be kept on the derrick floor during the drilling operation so that it can be readily applied when it is desired to close in the well either during operation or when the tubing is being run into position so as to flow the well when production has been obtained.

Other and further objects of the invention will be readily apparent when the following description is considered in connection with the accompanying drawing wherein:

Fig. 1 is a vertical sectional view illustrating the general arrangement and assembly of the parts and showing the inside of the head in section.

Fig. 2 is a side elevation of the head per se looking at the same from the left of Fig. 1.

'I'he well casing is indicated at 2 and is arranged to receive the closure assembly indicated generally at 3, which includes the anged coupling 4 which is shown as threaded at 5 to theA well casing. This coupling may be provided with a tapered seat 'I which can receive slips to support the pipe 8 which is positioned in the well.

A cap I0 is arranged to seat on the coupling 4 and may have a seal ring II therein which engages both the coupling and the cap I0. A plurality of bolts I2 hold these two parts together in uid tight relationship.

Above the cap Ill is the plug valve member I5 which includes a housing I6 shown as threaded at I'I to the cap I0. 'I'his housing I6 is of peculiar construction in order to receive the tubing plug valve I8 and the casing plug valve I9. The housing is generally cylindrical with a projecting portion 20 thereon and the inside of which is forced with a chamber 2|. A partition 22 closes the top of the chamber'2l except for the passage 23 from the casing and the passage 24 from the drill stem or tubing which is in the well. 5 This partition is shown as threaded at 25 in order to receive the pipe 8 so that the pipe may be` suspended from the head I6. p

The passage 23 is closed by the plug valve I3, when desired by turning the valve so that the 10 passage 2'IA therein is out of alignment with the passage 23. This rotation is accomplishedby means of the stem 28 which may have a wheel or wrench attached thereto in order to rotate the valve I9. A suitable stuiiing-box 28 forms a seal 15 about the plug valve and a hold-down ring 36 serves to retain the valve in position.

passage 24 to close the pipe 8. The passage 24 has a connection 36 thereon which is controlled by the valve 31 and leads into the cross-member 38 which forms part of the ow line 32.

A suitable gate valve 40 may be positioned in the line 32 and a pressure gauge 4I is arranged to record the well pressure. 35

The head will preferably be provided with projecting ears 42 so that it may be conveniently picked .up by an elevator or other hoisting equipment.

When the well is being drilled .it is desirable to be able to quickly close the casing as well as the string of drill pipe in the c asing in event the drill bit penetrates a formation carrying an excessive pressure. With this equipment the head l5 may be suitably supported in the corner of the Vderrick and in event an excessive pressure is encountered ,it may be lowered to position over the coupling 4.

rotated to connect the nipple 4I with the coupling Il.

If, on the other hand, the nipple II is carried by the pipe l then the -head will be rotated to engage the threads 2l. In either instance as soon as the pipe and the head are connected together the head is raised so that the slips may be removed from the bowl 'l and then the pipe suspended from the head is lowered until the head engages the coupling I, whereupon the bolts i! are then used to firmly anchor it in position.

The valves Il and Il can be turned to completely close the well until the flow line or other fitting can be connected thereto. The cap I0 may or may not be carried by the head II when it is suspended in the corner of the derrick, depending upon whether the threads i1 are to be engaged or the bolts I2 to be placed when it is desired to attach the head.

In event the pipe 8 constitutes the well tubing the same procedure may be followed and the head i5 used as the permanent cap for the well construction.

The advantage of the present construction is that the plug valves Il and i9 may be readily rotated to close of! the flow through the well head and the enormous body of material present prevents the cutting away of the valve which occurs in event a gate valve with the ordinary sliding type of gate is utilized.

What is claimed is:

1. A well head closure including a housing, a partition across said housing vclosing the top thereof, a plurality of vertical passages through said partition, rotatable plug valves in said partition closing each passage, and a tubing suspended from said partition at one of said passages.

2. A well head closure including a housing, means to attach said housing to the well casing head a partition across said housing closing the top thereof, a plurality of passages through said partition, rotatable plug valves in said partition and closing each passage, a tubing suspended from said partition at one of said passages, 'and a flow line connected to each of said passages above said partition and valves whereby said valves may control the ilow from the well casing or tubing.

3. The combination in a well head closure of a generally cylindrical housing to be attached to the well casing, means therein to suspend the well tubing within the casing, a passage through the top of said body from the tubing, a sidewardly projecting portion on said housing having a passage through the top of the body from the casing. a plug valve rotatable to close each of said passages, and a ilow line connected to each oi said passages.

4. A closure head for well casings comprising a body, means to connect said body to the well casing, an opening in said body to receive a flow of fluid from the well casing, a plurality oi outlet passages thru the top of said body from said opening, a valve in said body to control the iiow thru each of said passages, means to connect a flow line to each passage, and means to suspend a string of pipe in the wellcasing from at least one of said passages, said valves being plug valves.

5. A closure head for well casings comprising a body, means to connect said body to the well casing, an opening in said body to receive a flow oi' fluid from the well casing, a plurality of outlet passages thru the top of said body from said opening, a valve in said body to control the flow thru each of said passages, means to connect a flow line to each passage, and means to suspend a string of pipe in the well casing from at least one of said passages, said valves being plug valves which are axially aligned in said body.

FEUX L. PIVOTO. 

